A bis(o-aminophenol) compound is reacted with an aromatic dicarboxylic acid or an acid component containing an amide-formable derivative, thereby forming a polybenzoxazole. Polybenzoxazole is known to form an interlayer insulating film or surface-protective film for use in multi-layer wiring boards, etc. (see, for example, Japanese Patent Application Laid-Open (kokai) Nos. 2002-275264 and 5-102125).
Meanwhile, adamantane is a highly symmetric, stable compound by virtue of the structure thereof in which four cyclohexane rings are fused to form a cage-like skeleton. Adamantane exhibits low dielectric constant, which is characteristic to alicyclic compounds, and adamantane derivatives exhibit various functions. Therefore, adamantane and derivatives thereof are known to be useful sources for producing drugs, high-performance industrial materials, etc. Specifically, studies have been performed on production of optical elements such as optical disk substrates, optical fiber, and lenses from these compounds having optical characteristics and heat resistance (see, for example, Japanese Patent Application Laid-Open (kokai) Nos. 6-305044 and 9-302077). Application to photoresist resin sources of adamantane esters having acid-sensitivity, dry etching resistance, UV transparency, and other properties has been studied (see, for example, Japanese Patent Application Laid-Open (kokai) No. 4-39665).
In the meantime, in the field of semiconductor devices, lead-free solder and copper wiring have been employed in order to keep pace with the trend for micro-scaling of the devices. During packaging steps (e.g., encapsulation with resin, lead frame bonding, and wire bonding), LSI chips must be protected from heat and mechanical shock (e.g., 300° C. and 30 MPa). As a result, heat resistance of semiconductor devices per se has been of increasing importance in the production of the devices.
Furthermore, in the field of LSIs, there have been carried out micro-wiring for realizing high-speed operation and elevating integration degree through increase in the number of layers stacked. This raises the problem of signal delay called RC delay. Thus, interlayer insulating film or other elements are required to have lower dielectric constant.